filly has definitions from the field of zoology
1
[ noun ] (zoology) a young female horse under the age of four

Used in print

(The Sun, [Baltimore],...)

Gaining her second straight victory , Norman_B._Small_,_Jr. 's Garden_Fresh , a 3 - year old filly , downed promising colts in the $ 4500 St._Patrick's_Day_Purse , featured seventh race here today , and paid $ 7.20 straight .

Related terms

foal

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